It is known, according to FR-A 1 470 669, to prepare trifluoroethyl triflate (CF3SO3CH2CF3), referred to simply as “TfOTFE”, by reaction of 2,2,2-trifluoroethanol with triflyl chloride (CF3SO2Cl) in the presence of a base, such as triethylamine, and in an organic solvent which is dichloromethane.
The disadvantage from which this process suffers is that it results in highly polluting discharges due to the presence of large amounts of ammonium salt.
Provision has been made, according to EP-A 1 322 601, for a process for the sulfonylation of a hydroxylated organic compound which consists of reacting said compound with a sulfonylating agent in the presence of an effective amount of a Lewis acid.
The Lewis acid is a compound comprising a metal or semimetal cation regarded as “intermediate” in the “hardness” and “softness” classification defined by R. Pearson. Antimony chloride is an example of a Lewis acid suitable for the process described in EP-A 1 322 601.
Although this catalysis is highly advantageous, the Applicant Company was looking for a process involving commoner reactants.